HV2818/HV2918 No High-Voltage Bias, Low Harmonic Distortion, 32-Channel, High-Voltage Analog Switch Features General Description 32-channel (16 2:1 MUX) High-Voltage Analog The HV2818/HV2918 are low harmonic distortion, low Switch charge injection, 16 2:1 multiplexer/demultiplexer, high -voltage analog switches without high-voltage bias Only +5V Bias Supply Required supplies. They are intended for use in applications 3.3V and 5V CMOS Input Logic Level requiring high-voltage switching controlled by low- Asymmetric Switch Topology for Small Size voltage control signals, such as medical ultrasound 66 MHz Data Shift Clock Frequency imaging, driving piezoelectric transducers and Low-Parasitic Capacitance printers. Low Harmonic Distortion The HV2818/HV2918 are pin-to-pin compatible to DC to 50 MHz Analog Small-Signal Frequency high-voltage bias HV2801/HV2901, except for bias voltage pins. HV2818/HV2918 are available in a 64- 200 kHz to 50 MHz Large Signal Frequency pin, 9 x 9 mm QFN package. HV2818/HV2918 have -70 dB Typical Off Isolation at 5.0 MHz asymmetric topology to implement a small size in low Excellent Noise Immunity voltage bias high-voltage switches while keeping Cascadable Serial Data Register with Latches performance such as peak current. The SW pin can Integrated Bleed Resistors on the SW Outputs pass high-voltage pulsed signals when the switch is (HV2918 only) ON. During the OFF state, high-voltage should not be applied to the SW pin due to its asymmetric topology. Applications In medical ultrasound systems, the Y pin should be connected to the AFE (analog front end) and the SW Medical Ultrasound Imaging pin should be connected to a single piezoelectric Non-Destructive Testing (NDT) Metal Flaw transducer element to avoid high-voltage in the SW Detection pin during the switch OFF state. Piezoelectric Transducer Drivers HV2818 and HV2918 are identical, except for bleed Inkjet Printer Head resistors at SW pins. HV2818 does not have the bleed Optical MEMS Modules resistors at SW pins like HV2801. HV2918 has the bleed resistors at SW pins like HV2901. The bleed resistors eliminate possible voltage build-up on capacitive loads such as piezoelectric transducers. The ON/OFF state of the 32 switches is programmed individually through a digital serial interface. The devices only need a +5V low voltage bias supply. However, all of the analog switches can pass up to 100V high-voltage pulsed signals. Like other low voltage bias switches, the HV2818/HV2918 cannot pass high-voltage DC signals. They can only pass high -voltage pulsed signals up to 2.5 s pulse width. These devices have typical 6 ON resistance and 50 MHz bandwidth for small signals. 2020 Microchip Technology Inc. DS20006375A-page 1HV2818/HV2918 Package Type HV2818/HV2918 9 x 9 x 0.9 mm VQFN (TOP VIEW) 64 1 EP *Includes Exposed Thermal Pad (EP) see Table 2-1. Functional Block Diagram Bleed Output Level Switches Shifters Resistors Latches D SW0 LE CLR Y01 D LE CLR SW1 D SW2 LE CLR CLK Y23 D LE CLR 32-Bit SW3 D IN Shift Register D OUT D SW30 LE CLR Y3031 D LE CLR SW31 R V GND GND V DD LL DGND LE CLR HV2918 has bleed resistor at SWx pins DS20006375A-page 2 2020 Microchip Technology Inc.